Prototype System Research Articles

A Spatial Constraint Model for Manipulating Static Visualizations

We introduce a spatial constraint model to characterize the positioning and interactions in visualizations, thereby facilitating the activation of static visualizations. Our model provides users with the capability to manipulate visualizations through operations such as selection, filtering, navigation, arrangement, and aggregation. Building upon this conceptual framework, we propose a prototype system designed to activate pre-existing visualizations by imbuing them with intelligent interactions. This augmentation is accomplished through the integration of visual objects with forces. The instantiation of our spatial constraint model enables seamless animated transitions between distinct visualization layouts. To demonstrate the efficacy of our approach, we present usage scenarios that involve the activation of visualizations within real-world contexts.

To Pair or not to Pair? Machine-Learned Explicitly-Correlated Electronic Structure for NaCl in Water.

The extent of ion pairing in solution is an important phenomenon to rationalize transport and thermodynamic properties of electrolytes. A fundamental measure of this pairing is the potential of mean force (PMF) between solvated ions. The relative stabilities of the paired and solvent shared states in the PMF and the barrier between them are highly sensitive to the underlying potential energy surface. However, direct application of accurate electronic structure methods is challenging, since long simulations are required. We develop wave function based machine learning potentials with the random phase approximation (RPA) and second order Møller-Plesset (MP2) perturbation theory for the prototypical system of Na and Cl ions in water. We show both methods in agreement, predicting the paired and solvent shared states to have similar energies (within 0.2 kcal/mol). We also provide the same benchmarks for different DFT functionals as well as insight into the PMF based on simple analyses of the interactions in the system.

Miracle or Mirage? A Measurement Study of NFT Rug Pulls

NFT rug pull is one of the most prominent type of NFT scam, whose definition is that the developers of an NFT project abandon it and run away with investors' funds. Although they have drawn attention from our community, to the best of our knowledge, the NFT rug pulls have not been systematically measured. To fill the void, this paper presents the first in-depth measurement study of NFT rug pulls. Specifically, we first compile a list of 253 known NFT rug pulls as our initial confirmed rug pulls (i.e., ground truth), based on which we perform a pilot study, highlighting the key symptoms of NFT rug pulls. Then, we design an effective rule-based detector to measure the prevalence of NFT rug pulls in the ecosystem. We have labelled 7,487 happened NFT rug pull projects which were not revealed by our community. To eliminate the potential damage brought by rug pull scams, we take a step further towards designing a real-time prediction model to proactively identify the potential rug pull projects in an early stage ahead of the scam happens. We have implemented a prototype system, and deployed it in the real-world setting for over 6 months. Our system has raised alarms for 5,557 new NFT projects, which works as a whistle blower that pinpoints rug pull scams timely, thus mitigating the impacts.

An Emergent Quadruple Phase Ensemble in Doped Bismuth Ferrite Thin Films Through Site and Strain Engineering

AbstractIn ferroic materials, giant susceptibilities can be realized at artificially constructed phase boundaries through deterministic manipulation of the order parameter. Here, emergent ferroelectric structural phase evolution behavior is demonstrated through a synergistic combination of A‐site doping and strain engineering. Using chemical solution deposition derived (001)‐oriented Sm‐substituted bismuth ferrite (Bi1‐xSmxFeO3) films as a prototypical system, a morphotropic phase boundary comprising a coexistence of four distinct crystallographic phases is uncovered. These ferroelectric, polar, and nonpolar phases form a nanoscale mixture without the presence of crystallographically hard boundaries. The system thus possesses the ability to show both polarization rotation and extension, effectively releasing the polarization from its crystallographic constraint. Consequently, both robust ferroelectric properties and giant electromechanical responses are obtained. For instance, the optimized composition with x = 0.14 has a remnant polarization of 2Pr = 103 µC cm−2 and electromechanical response 175% that of undoped BFO. These findings showcase the tremendous potential of synthetic phase boundaries, particularly in the context of lead‐free functional multiferroics.

Development of a Multi-Robot System for Pier Construction

The construction industry is a challenging field for the application of robots. In particular, bridge construction, which involves many tasks at great heights, makes it difficult to implement robots. To construct a bridge, it is necessary to build numerous piers that can support the bridge deck. Pier construction involves a series of tasks including rebar connection, formwork installation, concrete pouring, formwork dismantling, and formwork reinstallation. These activities require working at heights, presenting a significant risk of falls. If bridge construction could be performed remotely using robots instead of relying on human labor, it would greatly contribute to the safety of bridge construction. This paper proposes a multi-robot system capable of remote operation and automation for rebar structure connection, concrete pouring, and concrete vibrating tasks in pier construction. The proposed multi-robot system for pier construction is composed of three robot systems. Each robot system consists of a robot arm mounted on a mobile robot that can move along rails. And to apply the proposed system to a construction site, it is essential to implement a compliance control algorithm that adapts to external forces. In this paper, we propose an admittance control that takes into account the weight of the tool for the compliance control of the proposed robot, which performs tasks by switching between various construction tools of different weights. Furthermore, we propose a synchronization control method for the multi-robot system to connect reinforcing structures. We validated the proposed algorithm through simulation. Furthermore, we developed a prototype of the proposed system to verify the feasibility of the suggested hardware design and control.

Hybrid renewable/grid power systems, an essential for base transceiver station penetration in Rural Nigeria

The energy crisis in Nigeria has continued to impede the rapid expansion of the telecommunication industry, whose operating expenditure is galloping due to over-dependence on diesel generators as an alternative source of power to its base transceiver station (BTS). This fossil-fuel power source has also increased the industry’s carbon footprint. As a solution to these problems, the objective of this work is to provide a sustainable and quality hybrid DC power supply system for BTS that would increase access to information and communication technology or ICT infrastructure. This involves the integration of solar & wind energy with the grid. The sizing of the hybrid sub-systems was designed & simulated using MATLAB Simulink to test for functionality. A prototype of the design system was then implemented with the results showing an average power output that guarantees 21 hours/day of supply. By installing this hybrid system of 1.3 kW, approximately 2.55 kg of diesel (C10H20) would be un-utilized by one BTS, thereby preventing 3.6 kg of CO2 from been emitted to the atmosphere daily. Extrapolating these values shows 930.75 kg of diesel can be saved and reduce 1314 kg of CO2 emission within a year. Hence eliminating the need for diesel-backup generator for a grid connected or non-grid BTS sited in rural areas.

Qigong Master: A Qigong-Based Attention Training Game Using Action Recognition and Balance Analysis

Baduanjin is a type of martial art that is aimed at the development and health of the physical, emotional and spiritual aspects. It emphasizes on gentle movements, relaxed yet disciplined, and training of mental concentration through relaxation. In order to make Baduanjin attention training more effective and easier, we proposed a novel Baduanjin-based attention training game that instructs the subject to practice Baduanjin using virtual reality (VR) and motion analysis. Through a virtual instructor who demonstrates a series of Baduanjin actions, the subject is asked to follow the instructor's movement at any time. Meanwhile, the 3D position of the subject's body joints is collected by a motion capture device for further analysis using a deep learning model to evaluate the order correctness and precision of the Baduanjin actions. In addition, transfer learning technique is used to solve the problem of small size of Baduanjin data. Preliminary tests with 20 normal individuals showed that the recognition accuracy of the Baduanjin actions reached nearly 97%, and the balance analysis reflected the position change of the body center of mass to a certain extent. We also compared the performance of the model with and without pre-training to demonstrate the importance of transfer learning. The result of these explorations shows the feasibility of this prototype system as an attention training system and its potential as an assistive treatment option. In conclusion, we not only created the virtual instructor that could provide accurate movement demonstration, but also collected objective action data for more accurate balance analysis to provide appropriate feedback.

IOT - Enabled Digital Vehicle Parking Systems using Machine Learning

Abstract: In large cities, parking availability is a major problem. Car owners are confused by crowded reserved parking spaces during rush hour. To overcome this obstacle, modernizing the parking system is crucial. This research will conduct an in-depth and thorough literature review of past studies and project implementations to identify best practices and gaps in the existing research. The goal is to analyze previous work comprehensively, highlighting successful approaches and areas where further investigation is needed.In this study aims to perform a detailed and comprehensive examinations of previous research and research executions to precise effective strategies and deficiencies in the current body of research.The objective is to thoroughly evaluate prior efforts,emphasizing successful methodologies and areas requiring additional investigation.A prototype of the digital vehicle Parking System is implemented via an Android application leveraging Firebase and IoT based on AI . This makes it easy for drivers to find parking spaces with assigned spaces.

Overview of Hand Sign Recognition System

Abstract: Hand gesture is one of the methods used in sign language for non-verbal communication. It is most commonly used by deaf & dumb people who have hearing or speech problems to communicate among themselves or with normal people. Various sign language systems have been developed by many makers around the world but they are neither flexible nor cost-effective for the end users. Hence, it is software that presents a system prototype that can automatically recognize sign language to help deaf and dumb people communicate more effectively with each other or normal people. Dumb people are usually deprived of normal communication with other people in society, also normal people find it difficult to understand and communicate with them. These people have to rely on an interpreter or some sort of visual communication. An interpreter won’t be always available and visual communication is mostly difficult to understand. Sign Language is the primary means of communication in the deaf and dumb community. As a normal person is unaware of the grammar or meaning of various gestures that are part of sign language, it is primarily limited to their families and/or deaf and dumb community

Impact of nuclear effects on the ultrafast dynamics of an organic/inorganic mixed-dimensional interface

Electron dynamics at weakly bound interfaces of organic/inorganic materials are easily influenced by large-amplitude nuclear motion. In this work, we investigate the effects of different approximations to the equilibrium nuclear distributions on the ultrafast charge-carrier dynamics of a laser-excited hybrid organic/inorganic interface. By considering a prototypical system consisting of pyrene physisorbed on a MoSe2 monolayer, we analyze linear absorption spectra, electronic density currents, and charge-transfer dynamics induced by a femtosecond pulse in resonance with the frontier-orbital transition in the molecule. The calculations are based on ab initio molecular dynamics with classical and quantum thermostats, followed by time-dependent density-functional theory coupled to multi-trajectory Ehrenfest dynamics. We impinge the system with a femtosecond (fs) pulse of a few hundred GW cm−2 intensity and propagate it for 100 fs. We find that the optical spectrum is insensitive to different nuclear distributions in the energy range dominated by the excitations localized on the monolayer. The pyrene resonance, in contrast, shows a small blue shift at finite temperatures, hinting at an electron-phonon-induced vibrational-level renormalization. The electronic current density following the excitation is affected by classical and quantum nuclear sampling through suppression of beating patterns and faster decay times. Interestingly, finite temperature leads to a longer stability of the ultrafast charge transfer after excitation. Overall, the results show that the ultrafast charge-carrier dynamics are dominated by electronic rather than by nuclear effects at the field strengths and time scales considered in this work.

Wireless End to End Image Transmission System using Li-Fi Technology

The first and most important objective of this project is to convey the image through the utilization of a light-emitting diode (LED). The innovative technique known as visible light communication (VLC) holds enormous promise for the implementation of high-speed, large-capacity, short-range wireless data transmission. It is gaining popularity on account of the growing use of solid-state lighting systems. Additionally, LED lights change frequency at a rate that is substantially faster than what the human eye is able to perceive. This is in addition to the fact that radio waves have a higher repetition rate than LED lights, which results in significantly greater speed than Wi-Fi. This work suggests a real-time image broadcast system prototype. Light-emitting diode (LED) lights are used in the prototype since they are widely available and reasonably priced. The scope of the work encompasses the possibility of making information and communication accessible through the utilization of LED bulbs in a manner that may be implemented in a variety of situations, such as homes, offices, organizations, and corporations. If the LED sources are positioned correctly and concentration effects are increased, it is feasible to obtain a real-time image with a maximum distance of two feet, according to the testing results. In addition to being made to last, the LI-FI (Light Fidelity) light source features a broad variety of digital settings that can be adjusted, and it is simple to operate as a result of its efficient design

Insights into the development of a landslide early warning system prototype in an informal settlement: the case of Bello Oriente in Medellín, Colombia

Abstract. The global number of vulnerable citizens in areas of landslide risk is expected to increase due to the twin forces of climate change and growing urbanization. Self-constructed or informal settlements are frequently built in hazardous terrain such as on landslide-prone slopes. They are characterized by high dynamics of growth, simple construction methods and strong social dynamics and are exposed to unsteady political approaches. Landslide early warning systems (LEWSs) can contribute to decreasing their vulnerability, but precise, affordable and culturally integrated LEWSs need to be further developed. In this paper, we present a 4-year living-lab research project called Inform@Risk that aimed to develop a LEWS prototype in the neighborhood of Bello Oriente, located on the urban–rural border of Medellín, Colombia. Its research team is composed of landscape architects, geo-engineers, and remote sensing and geo-informatics experts. The research team collaborated with a multitude of stakeholders: civil society, private enterprises, non-governmental agencies and various branches of government. A preliminary LEWS with the last functionalities still to be developed has been designed, implemented and handed over to the government. It has entered a test and calibration phase (i.e., warning-threshold development, procedures for warning and alert dissemination through the sensor system), which is on hold due to legal constraints. Our first findings indicate that the integrative development of technical aspects of a LEWS in informal settlements can be challenging, albeit manageable, whereas the level of social and political support is beyond the control of the designer. Steady political will is needed to increase technical capacities and funding of the operation and maintenance of an increased amount of monitoring equipment. Social outreach has to be continuous in order to inform, train, maintain the trust and increase the self-help capacities of the often rapidly changing population of an informal settlement. Legal requirements for a transfer of academic research projects to municipal authorities have to be clear from the start. Satisfying replacement housing options for the case of evacuation have to be in place in order to not lose the overall acceptance of the LEWS. As political will and municipal budgets can vary, a resilient LEWS for informal settlements has to achieve sufficient social and technical redundancy to maintain basic functionality even in a reduced-governmental-support scenario.

Background discrimination with a Micromegas detector prototype and veto system for BabyIAXO

In this paper we present measurements performed with a Micromegas X-ray detector setup. The detector is a prototype in the context of the BabyIAXO helioscope, which is under construction to search for an emission of the hypothetical axion particle from the Sun. An important component of such a helioscope is a low background X-ray detector with a high efficiency in the 1–10 keV energy range. The goal of the measurement was to study techniques for background discrimination. In addition to common techniques we used a multi-layer veto system designed to tag cosmic-ray induced neutron background. Over an effective time of 52 days, a background level of 8.6 × 10−7 counts keV−1 cm−2 s−1 was reached in a laboratory at above ground level. This is the lowest background level achieved at surface level. In this paper we present the experimental setup, show simulations of the neutron-induced background, and demonstrate the process to identify background signals in the data. Finally, prospects to reach lower background levels down to 10–7 counts keV−1 cm−2 s−1 are discussed.

Integrated Extended Kalman Filter and Deep Learning Platform for Electric Vehicle Battery Health Prediction

As the demand for electric vehicles (EVs) rises globally, ensuring the safety and reliability of EV battery systems becomes paramount. Accurately predicting the state of health (SoH) and state of charge (SoC) of EV batteries is crucial for maintaining their safe and consistent operation. This paper introduces a novel approach leveraging deep learning methodologies to predict battery SoH, focusing on implementing a system prototype for real-world applications. The proposed system integrates an extended Kalman filter (EKF) with a deep learning framework, forming a system prototype known as FELL, aimed at EV battery diagnosis and prediction. We devise an algorithm utilizing the EKF to estimate the SoH of the battery. We present a detailed overview of the system architecture and implementation, showcasing its predictive capabilities. Experimental results demonstrate the effectiveness of the system in accurately estimating battery SoH with notable improvements in prediction accuracy. Additionally, the FELL system provides users with real-time predictions and comparative analysis across multiple prediction models, offering valuable insights for EV battery management.

3D Pop-Ups: Omnidirectional image visual saliency prediction based on crowdsourced eye-tracking data in VR

The prediction of the visual saliency of omnidirectional images in VR is valuable for understanding visual behaviors. However, the equipment cost, software setups, hardware operation, and other constraints in acquiring eye-tracking data of omnidirectional images for visual saliency prediction would lead to a low training efficiency and prediction performance. Therefore, this paper proposed a crowdsourcing method based on recall fixations, which was used to collect and construct an omnidirectional image with eye-tracking dataset called CrowdSourcing360, which contained 16,200 pieces of data on 180 images. Using this dataset, a visual saliency prediction model CSnet360 was trained. Experiments demonstrated that the visual saliency prediction performance of the CSnet360 outperformed most existing models even without using actual gaze fixations. Finally, a VR interior design assistance prototype system was built and the preliminary study results indicated that the system could help designers to improve the quality of their design solutions.

Photodetachment and Tunneling Dissociation of Cryogenic Double-Rydberg Anions NH4.

The Rydberg radical NH4 and the double Rydberg anion (DRA) NH4- have long aroused researchers' interests due to their potential for exploring the reaction dynamics of the H + NH3 → H2 + NH2 reaction, a prototypical penta-atomic system. In this study, we present high-resolution photodetachment spectroscopy of DRA NH4- and ion-molecule complex H-(NH3). We observed multiple new photodetachment channels of DRA NH4-. The energy level of the excited state (3p 2T2) of the Rydberg radical NH4 was determined to be 15052(94) cm-1, in excellent agreement with the principal Schüler band (15061.61 cm-1). Additionally, we observed the tunneling dissociation of NH4- in a cryogenic ion trap with its dissociation lifetime determined to be 19(2) ms.

Repository of MRI-derived models of the breast with single and multiple benign and malignant tumors for microwave imaging research.

The diagnosis of breast cancer through MicroWave Imaging (MWI) technology has been extensively researched over the past few decades. However, continuous improvements to systems are needed to achieve clinical viability. To this end, the numerical models employed in simulation studies need to be diversified, anatomically accurate, and also representative of the cases in clinical settings. Hence, we have created the first open-access repository of 3D anatomically accurate numerical models of the breast, derived from 3.0T Magnetic Resonance Images (MRI) of benign breast disease and breast cancer patients. The models include normal breast tissues (fat, fibroglandular, skin, and muscle tissues), and benign and cancerous breast tumors. The repository contains easily reconfigurable models which can be tumor-free or contain single or multiple tumors, allowing complex and realistic test scenarios needed for feasibility and performance assessment of MWI devices prior to experimental and clinical testing. It also includes an executable file which enables researchers to generate models incorporating the dielectric properties of breast tissues at a chosen frequency ranging from 3 to 10 GHz, thereby ensuring compatibility with a wide spectrum of research requirements and stages of development for any breast MWI prototype system. Currently, our dataset comprises MRI scans of 55 patients, but new exams will be continuously added.

Radiationless decay spectrum of O 1s double core holes in liquid water.

We present a combined experimental and theoretical investigation of the radiationless decay spectrum of an O 1s double core hole in liquid water. Our experiments were carried out using liquid-jet electron spectroscopy from cylindrical microjets of normal and deuterated water. The signal of the double-core-hole spectral fingerprints (hypersatellites) of liquid water is clearly identified, with an intensity ratio to Auger decay of singly charged O 1s of 0.0014(5). We observe a significant isotope effect between liquid H2O and D2O. For theoretical modeling, the Auger electron spectrum of the central water molecule in a water pentamer was calculated using an electronic-structure toolkit combined with molecular-dynamics simulations to capture the influence of molecular rearrangement within the ultrashort lifetime of the double core hole. We obtained the static and dynamic Auger spectra for H2O, (H2O)5, D2O, and (D2O)5, instantaneous Auger spectra at selected times after core-level ionization, and the symmetrized oxygen-hydrogen distance as a function of time after double core ionization for all four prototypical systems. We consider this observation of liquid-water double core holes as a new tool to study ultrafast nuclear dynamics.

Three-component systems represent a common pathway for extracytoplasmic addition of pentofuranose sugars into bacterial glycans

Cell surface glycans are major drivers of antigenic diversity in bacteria. The biochemistry and molecular biology underpinning their synthesis are important in understanding host-pathogen interactions and for vaccine development with emerging chemoenzymatic and glycoengineering approaches. Structural diversity in glycostructures arises from the action of glycosyltransferases (GTs) that use an immense catalog of activated sugar donors to build the repeating unit and modifying enzymes that add further heterogeneity. Classical Leloir GTs incorporate α- or β-linked sugars by inverting or retaining mechanisms, depending on the nucleotide sugar donor. In contrast, the mechanism of known ribofuranosyltransferases is confined to β-linkages, so the existence of α-linked ribofuranose in some glycans dictates an alternative strategy. Here, we use Citrobacter youngae O1 and O2 lipopolysaccharide O antigens as prototypes to describe a widespread, versatile pathway for incorporating side-chain α-linked pentofuranoses by extracytoplasmic postpolymerization glycosylation. The pathway requires a polyprenyl phosphoribose synthase to generate a lipid-linked donor, a MATE-family flippase to transport the donor to the periplasm, and a GT-C type GT (founding the GT136 family) that performs the final glycosylation reaction. The characterized system shares similarities, but also fundamental differences, with both cell wall arabinan biosynthesis in mycobacteria, and periplasmic glucosylation of O antigens first discovered in Salmonella and Shigella. The participation of auxiliary epimerases allows the diversification of incorporated pentofuranoses. The results offer insight into a broad concept in microbial glycobiology and provide prototype systems and bioinformatic guides that facilitate discovery of further examples from diverse species, some in currently unknown glycans.

Participatory design of a virtual reality life review therapy system for palliative care

We present a novel Virtual Reality (VR) life review therapy system. Life review therapy is an intervention used by clinical psychologists, counselors, and social workers for patients under palliative care to systematically examine various life experiences to resolve conflicts and complete life tasks. The goal of the therapy is to narrativize the patient’s life before death in order to come to terms with their mortality. Our VR life review therapy system allows therapists to perform their interventions in customized virtual spaces designed to encourage the patient to reflect and reminisce about their life experiences. Our system is also developed in response to mobility restrictions and COVID-19 pandemic-related quarantine measures that have separated patients under palliative care from family and friends, resulting in emotional and psychological distress. As VR systems related to health are increasingly being used by therapists in their interventions, it is of utmost importance that the health professionals who will be the end users of these systems are involved in the design process to create ethical healthcare technologies. In response, we initiated the participatory design and evaluation of our VR life review therapy system prototype with six clinical psychologists who have practical experience delivering life review therapy to patients in palliative care in the Hong Kong hospital system. In the study, each participant experienced the VR life review therapy system and evaluated its strengths and weaknesses through semi-structured interviews. The qualitative data gathered from these interviews was coded according to nine different categories; avatars, content design, evaluation, haptic sensations, interaction, gesturing and gaze direction, movement and navigation, non-verbal communication, soundtrack. These conceptual categories were chosen based on our analysis of common themes reported by the clinical psychologists’ experience of the system. Feedback from clinical psychologists on each of these categories was incorporated into the redesign and update of the final system. Overall, participants generally evaluated the system as feasible and effective for use with patients under palliative care, while movement and interaction were the features requiring the most improvement.